Scripting Ocellaris

There are three main ways of scripting Ocellaris:

  1. Generate input files by a script and run Ocellaris on these

  2. Include Python code in the input file (see the User Guide for details)

  3. Use the Python programming interface

A brief example of the first would be something like this that runs Ocellaris with two different time steps by producing input files and starting Ocellaris as a command line application:

import yaml, subprocess

# Load the template input file
with open('template.inp', 'rt') as inp:
    input_dict = yaml.load(inp)

for dt in [0.1, 0.05]:
    # Modify the input file
    prefix = 'test_dt_%.3f' % dt
    input_dict['time']['dt'] = dt
    input_dict['output']['prefix'] = prefix

    # Save the modified input file
    new_inp_file = prefix + '.inp'
    with open(new_inp_file, 'wt') as out:
        yaml.dump(input_dict, out)

    # Run Ocellaris with the modified input file
    p = subprocess.Popen(['python', '-m', 'ocellaris', new_inp_file],
                         stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    stdout, stderr = p.communicate()

The same can be accomplished from a script which uses the Ocellaris Python API:

from ocellaris import Simulation, setup_simulation, run_simulation

for dt in [0.1, 0.05]:
    prefix = 'test_dt_%.3f' % dt

    # Create a simulation object, load an input file and modify the time step
    sim = Simulation()
    sim.input.set_value('time/dt', dt)
    sim.input.set_value('output/prefix', prefix)

    # Run Ocellaris

For more information about what you can do with the simulation object, see the Simulation classes API documentation.

Examples of this can be seen in the convergence scripts which can be found in the cases/ subdirectory of the Ocellaris repository.